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Hey everybody,

I'm using the provided code examples from TI in combination with the MSP430 and CC1101.While having most of CC1101's registers set like I want to and transmitting data successfully, it is not possible for me to set up fixed packet length.

When I change* the PKTCTRL0 - Packet Automation Control::LENGTH_CONFIG bytes to 0 (00) -fixed packet length- and leave the PKTLEN::PACKET_LENGTH register with its preset value ( I guess 58 bytes**) while normally sending just following packet:

[1 byte - Length][4 byte - DSTADDR][4 byte - SRCADDR][1 byte - App Payload]

..the transmission breaks completely down. It seems that the transmitter is still sending while the receiver refuses to recognise that at all.

Do I miss something?!

Do I have to 'fill' all the empty 'bytes'? (I thought this value is just an upper limit and all shorter packets will be still detected)

Or in other words, adjusting the PKTLEN, how many bytes would that be in my case to set - just 9? => [4 byte - DSTADDR][4 byte - SRCADDR][1 byte - App Payload]

..assuming that the packet Length byte gets removed so that (according to the frame structure **) the DSTADDR and SRCADDR address bytes gets 'left shifted' by 1 byte?

How does the receiver know the end of the transmitted packet? E.g. a  9 byte long packet is expected but a 10 byte long was sent. Does the receiver rejects the whole packet or just forwarding 9 of the 10 byte?

Any help is appreciated.

beste regards, FT

* of course on both, rx and tx sides

** for calculating the adequate packet length MRFI_SETTING_PKTLEN the code (MRFI_MAX_FRAME_SIZE - MRFI_LENGTH_FIELD_SIZE) in mrfi_radio.c first adds MRFI_LENGTH_FIELD_SIZE and than subtracts it again (see code line) - why is that?!

*** see SimpliciTI: Simple Modular RF Netwok Specification, Figure 7: SimpliciTI frame structure (w/o..), p.11